Toy vehicle wireless control system

ABSTRACT

A toy vehicle remote control transmitter unit wirelessly controls the movements of a programmable toy vehicle. The toy vehicle includes a motive chassis having a plurality of steering positions. A microprocessor in the transmitter unit emulates manual transmission operation of the toy vehicle by being in any one of a plurality of different gear states selected by an operation of manual input elements on the transmitter unit. Forward propulsion control signals representing different toy vehicle speed ratios associated with each of the gear states are transmitted from the transmitter unit to the toy vehicle. The motive chassis has a steering feedback sensor with a plurality of defined steering positions to vary rate of steering position change to avoid overshoot.

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. ProvisionalApplication No. 60/340,591, filed Oct. 30, 2001, entitled “Toy VehicleWireless Control System,” which is incorporated herein by reference inits entirety.

BACKGROUND OF THE INVENTION

[0002] This invention relates to toy vehicles and, in particular, toremotely controlled, motorized toy vehicles.

SUMMARY OF THE INVENTION

[0003] The invention is in a toy vehicle remote control transmitter unitincluding a housing, a plurality of manual input elements mounted on thehousing for manual movement, a microprocessor in the housing operablycoupled with each manual input element on the housing, and a signaltransmitter operably coupled with the microprocessor to transmitwireless control signals generated by the microprocessor to a toyvehicle. The invention is characterized in that the microprocessor isconfigured for at least two different modes of operation. One of themodes emulates manual transmission operation of the toy vehicle by beingin any one of a plurality of different gear states and transmittingthrough the transmitter forward propulsion control signals representingdifferent speed ratios for each of the plurality of different gearstates. The microprocessor is further configured to consecutivelyadvance through the different gear states in response to successivemanual operations of at least one of the manual input devices.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

[0004] The following detailed description of preferred embodiments ofthe invention, will be better understood when read in conjunction withthe appended drawings. For the purpose of illustrating the invention,there is shown in the drawings embodiments which are presentlypreferred. It should be understood, however, that the invention is notlimited to the precise arrangements and instrumentalities shown. In thedrawings:

[0005]FIG. 1A is a top plan view of an exemplary remotecontrol/transmitter used in accordance with the present invention;

[0006]FIG. 1B is an exemplary toy vehicle remotely controlled by theremote control/transmitter of FIG. 1A;

[0007]FIG. 2 is a timing diagram showing an analog output of a controlcircuit used to drive different motor speeds of the toy vehicle of FIG.1B in accordance with a preferred embodiment of the present invention;

[0008]FIG. 3 is a diagram showing a trapezoidal velocity profile of asteering finction of the toy vehicle of FIG. 1B;

[0009]FIG. 4 is a schematic diagram of a control circuit in the toyvehicle of FIG. 1B, which is directly responsive to steering commandsreceived in accordance with the present invention;

[0010]FIG. 5 is a schematic diagram of a speed shifter remotecontrol/transmitter circuit which sends steering commands to the controlcircuit of FIG. 4;

[0011]FIGS. 6A, 6B, 6C and 6D, taken together, is a flow chartillustrating the operation of the vehicle control circuit of FIG. 4;

[0012]FIGS. 7A, 7B, 7C, 7D, 7E, 7F, 7G, 7H, 7I and 7J, taken together,is a flow chart illustrating the operation of the speed shifter remotecontrol/transmitter circuit of FIG. 5;

[0013]FIGS. 8A, 8B, 8C, 8D and 8E, taken together, is a schematicdiagram of a toy vehicle control circuit which processes receivedsteering commands based on current steering position of the toy vehiclein accordance with an alternate embodiment of the present invention;

[0014]FIGS. 9A and 9B, taken together, is a schematic diagram of a speedshifter remote control/transmitter circuit in accordance with analternate embodiment of the present invention;

[0015]FIG. 10A depicts a steering output assembly;

[0016]FIG. 10B depicts the assembly of FIG. 10A with the output memberand reduction gearing removed; and

[0017]FIG. 11 depicts the stationary portion or contact member of asteering sensor.

DETAILED DESCRIPTION OF THE INVENTION

[0018] Related U.S. Application No. 60/340,591 filed Oct. 30, 2001 isincorporated by reference herein. The present invention is a toy vehiclewireless control system which includes a remote control/transmitter 100(FIG. 1A) with a speed shifter remote control/transmitter circuit 500(see FIG. 5) or 900 (see FIGS. 9A, 9B), and a remotely controlled toyvehicle 20 (FIG. 1B) with a receiver/microprocessor based toy vehiclecontrol circuit 400 (see FIG. 4) or 900 (see FIGS. 9A-9E), alsohereinafter referred to as a speed shifter receiver circuit.

[0019] The remote control/transmitter 100 depicted in FIG. 1A includes ahousing 105 and a plurality of manual input elements 110, 115 mounted onhousing 105 and used for controlling the manual movement of a toyvehicle 20. The manual input elements 110, 115 are conventionally usedto supply propulsion or movement commands and steering commands,respectively. They also enable selection among three different modes ofoperation or usage (hereinafter referred to as “Mode 1,” “Mode 2,” and“Mode 3”), each having a different play pattern. Power is selectivelyprovided to circuitry in the remote control/transmitter 100 via ON/OFFswitch 135 (in phantom in FIG. 1A).

[0020] Car 20 is shown in FIG. 1B and includes a chassis 22, body 24,rear drive wheels 26 operably coupled to drive/propulsion motor 420(phantom) and front free rotating wheels 28 operably coupled withsteering motor 410 (phantom). An antenna 30 receives command signalsfrom remote control/transmitter 10 and carries those signals to thevehicle control circuit 400 (phantom) or 800 (not shown in FIG. 1B). Anon-off switch 450 turns the circuit 400 on and off, and a battery powersupply 435 provides power to the circuit 400 and motors 410, 420.

[0021]FIG. 4 shows a schematic diagram of a vehicle control circuit 400in the toy vehicle 20. The vehicle control circuit 400 includes asteering motor control circuit 405 which controls steering motor 410,and a propulsion motor control circuit 415 which controls drive motor420. Microprocessor 4U1 is in communication with steering motor anddrive motor control circuits 405, 415, and controls all other functionsexecuted within the toy vehicle 20. A vehicle receiver circuit 430receives control signals sent by remote control/transmitter 100 andamplifies and sends the control signals to microprocessor 4U1 forprocessing. A power supply circuit 440 powers the vehicle controlcircuit 400 in toy vehicle 20 and the steering and propulsion motors410, 420, respectively.

[0022]FIG. 5 shows a transmitter circuit 500 in the remotecontrol/transmitter 100 (see FIG. 1A) that is powered by a battery 505in communication with a two-position switch 135 that is used to turn thedevice 100 on and off and for selecting one of the modes. Thetransmitter circuit 500 also includes a microprocessor 5U1. Themicroprocessor 5U1 is operably coupled with each of the manual inputelements 110, 115. The remote control/transmitter 100 must first beturned off via switch 135 to change the mode used. Manual input element110 is preferably a center biased rocker button operating momentarycontact switches 110 a and 110 b, as shown in FIG. 5. When pressed, themanual input element 110 causes one of contact switches 110 a and 110 bto change states. This is sensed by the microprocessor 5U1 whichresponds by transmitting a signal via antenna 120 to cause remotelycontrolled toy vehicle 20, which includes receiver/microprocessor 4U1,to move forward or backward. Manual input element 115 is also preferablya center biased rocker button operating momentary contact switches 115 aand 115 b in FIG. 5 which, when pressed, causes the remotecontrol/transmitter 100 to transmit via antenna 120 a command toreceiver/microprocessor 4U1 causing the toy vehicle 20 to steer to theleft or to the right. When manual input element 115 is not pressed (i.e.in center position), the toy vehicle 20 travels in a straight path. Whenthe manual input element 110 is not pressed, the vehicle 20 stops.

[0023] Mode 1, a first mode of operation or usage, is the default modeachieved when the remote control/transmitter 100 is activated from adeactivated state by moving on-off switch 135 in FIG. 5 from an “off”position to an “on” position. This mode has a multiple-speed (3-speed inthe present embodiment) manual gear-shifting play pattern in which themicroprocessor 5U1 emulates a manual transmission operation of the toyvehicle 20 and in which corresponding sounds are generated by themicroprocessor 5U1 and played on a speaker 125 in the remotecontrol/transmitter 100. Mode 1 has the following features andcharacteristics:

[0024] (1) The motionless toy vehicle 20 is put into motion by pressingmanual input element 110 to a “forward” button position, closing orotherwise changing the nominal state of switch 110 a on the remotecontrol/transmitter 100. The microprocessor 5U1 is configured (i.e.,programmed) to respond to the depressions of manual input element 110 byentering a first gear state of operation and generating a first forwardmovement command signal transmitted to the toy vehicle 20. Initially,the toy vehicle 20 responds to the first signal and moves forward at afirst top speed which is less than a maximum speed the toy vehicle 20 iscapable of running. The microprocessor 5U1 generates a first sound,which is outputted by speaker 125, to simulate first gear operation ofthe toy vehicle 20.

[0025] (2) Once the toy vehicle 20 is moving forward for a while in afirst gear state (as timed by microprocessor 5U1), a visual indication(e.g., red flashing LED 130) and/or an audible sound (e.g., single hornbeep) can be outputted by the microprocessor 5U1 from the remotecontrol/transmitter 100 to signal to a user that it is OK to shift tothe second gear. Shifting into a higher gear is performed by momentarilyreleasing and re-engaging the forward button position of manual inputelement 110, which closes switch 110 a within a predetermined timewindow. If the time window elapses, the toy vehicle 20 will return tofirst gear state when the forward button position of manual inputelement 110 is activated (i.e., switch 110 a is closed). Once in thesecond gear state, the microprocessor 4U1 commands the vehicle 20 tomove forward at a second top speed that is faster than the first topspeed but less than maximum speed, and preferably the microprocessor 5U1generates a second sound which is outputted by speaker 125 to simulatesecond gear operation of the toy vehicle 20. Once the toy vehicle 20 ismoving forward for a while in a second gear state, a visual indication(e.g., red flashing LED 130) and/or an audible sound (e.g., single hornbeep) can be outputted by microprocessor 5U1 from speaker 125 of theremote control/transmitter 100 to signal to a user that it is OK toshift to the third gear. The forward button position of input element110 closing switch 110 a is again momentarily released and re-engagedwithin a predetermined time window. If the time window elapses, the toyvehicle 20 will return to first gear when the forward button position ofmanual input element 110 is activated. Once in the third gear state, thetoy vehicle 20 moves forward at a third top speed that is faster thanthe second top speed, and preferably the microprocessor 5U1 generates athird sound that is outputted by speaker 125 to simulate third gearoperation of the toy vehicle 20. The movement of the toy vehicle 20 isterminated by releasing the forward button position of manual inputelement 110 closing switch 110 a or by pressing and then releasingreverse button position of manual input element 110 closing switch 110b.

[0026] (3) In the three-speed embodiment, preferably the top speed ofthe toy vehicle 20 may be 62.5% of maximum speed when in the first gearstate, 75% of maximum speed when in the second gear state, and 100% ofmaximum speed when in the third gear state. Other ratios and/oradditional ratios to provide four, five, six or more speeds can be usedto simulate other car and truck shifting.

[0027] (4) If the gear state of the toy vehicle 20 is changed before thetoy vehicle 20 reaches its top speed for the previous gear bymomentarily releasing and re-engaging the forward button position ofmanual input element 110, before the microprocessor 5U1 opens thepredetermined time window to shift, the microprocessor 5U1 generates adifferent audible sound (e.g., grinding noise), which is preferablyoutputted by the speaker 125 of the remote control/transmitter 100, tosignal that the user shifted too early. Top speed is not increased.

[0028] (5) Various audible sounds (e.g., peel out, squealing tire, hardbraking, accelerating motor, etc.) are preferably outputted by theremote control/transmitter 100 in response to activating the manualinput elements 110, 115 on the remote control/transmitter 100. Forexample, transmitting a steering command by causing manual input element115 to close switch 115 a while the toy vehicle 20 is moving (e.g.,forward position of manual input element 110 being pressed changing thestate of switch 110 a) causes the microprocessor 5U1 to output anaudible sound (e.g., the squealing of tires) through speaker 125. Thereis a small delay in producing the audible sound so that small steeringcorrections do not cause the audible sound to be outputted by speaker125. Releasing either the forward and reverse position of manual inputelement 110 preferably causes the microprocessor 5U1 to output anaudible sound (e.g., hard breaking, tire screeching) through speaker125. An “idling” sound is then preferably outputted by microprocessor5U1 through speaker 125 until a next propulsion/drive command istransmitted.

[0029] (6) Speed of the toy vehicle 20 is controlled by the remotecontrol/transmitter 100 outputting propulsion control signals having PWM(Pulse Width Modulation) characteristics with duty cycles approximatefor the speed ratios selected, e.g., 56%, 75%, and 100% (see FIG. 2).Preferably, the remote control/transmitter 100 outputs a binary signalwith two or more values allocated to propulsion commands. Two binarybits can be used to identify stop and three forward speed values (e.g.,first, second and third speeds). The vehicle microprocessor 4U1 ispreferably programmed to power each motor 410, 420 according to a dutycycle identified by the binary bits. Referring to FIG. 2, a fixed timeperiod (e.g. sixteen milliseconds) can be broken up into fractions(e.g., sixteen, one millisecond parts) and power (V hi) supplied to themotor for the fraction of the time period (e.g., {fraction (0/16)},{fraction (10/16)}, {fraction (12/16)}, {fraction (16/16)}) commanded bythe two binary bits. An {fraction (8/16)} duty cycle is depicted, with Vhi provided for eight parts and V low (i.e. 0 Volts) provided for theremaining eight parts of the period constituting the cycle. If threebits are allocated to propulsion commands, a stop command and sevendifferent forward and reverse speed commands can be encoded. Preferably,reverse speed is at a ratio of less than 100% for ease of vehiclecontrol and realism.

[0030] Mode 2 is achieved by turning on switch 135 of the remotecontrol/transmitter 100 while holding manual input element 110 in a“forward” movement position (changing the state of switch 110 a) on theremote control/transmitter 100 until the microprocessor 5U1 acknowledgesthe command by causing the speaker 125 to output an audible sound (e.g.,horn beeps) and/or the red LED 130 to flash. This mode allows the userto maneuver the toy vehicle 20 in the usual manner with sounds beinggenerated but no gear shifting operation. The microprocessor 5U1 ispreferably preprogrammed for a desired default speed, e.g., 100% forwardand 50% or 100% reverse.

[0031] Mode 3 is achieved by turning on switch 135 of the remotecontrol/transmitter 100 while holding manual input element 110 in a“reverse” movement position (i.e. changing state of the switch 110 b) onthe remote control/transmitter 100 until the microprocessor 5U1 causesspeaker 125 to output an audible sound (e.g., horn beeps) and/or the redLED 130 to flash. This mode allows the user to maneuver the toy vehicle20 in the usual manner with no sound generation by microprocessor 5U1 orgear shifting operation. The microprocessor 5U1 is preprogrammed for adesired default speed, e.g., 100% forward and 50% or 100% reverse.

[0032] A “Try Me Mode” may be provided, if desired, allowing only soundeffects of the remote control/transmitter 100 to be produced while stillin its packaging. Sound effects are generated by pressing any button onthe transmitter. Pushing the manual input element 110 to the “forward”position can cause the start-up sound to play followed by a peel-outsound with both motor and shifting sounds. Pushing the manual inputelement 110 to the “reverse” position can cause the horn sound to playwith the motor running sound. Pushing the manual input element 15 “left”and “right” can activate the squealing tire sound accompanied by theengine downshift sound. The “Try Me Mode” preferably is deactivatedautomatically when the toy is taken out of its packaging and a pull-tabis removed from the remote control/transmitter 100, allowing thetransmitter 100 and toy vehicle 20 to be operated in one of the threemodes described above.

[0033] FIGS. 7A-7J depict the various steps of an operating program 700contained by the transmitter circuit 500, such as by firmware orsoftware in the microprocessor 5U1, to operate the remotecontrol/transmitter 100 in the multiple modes of operation and in thedifferent shift states in the first mode of operation. Again, themicroprocessor 5U1 is preferably configured to transmit commands inbinary form with propulsion and/or steering commands encoded as binarybits or sets of such bits.

[0034] FIGS. 6A-6C depict the various steps of an operating program 600contained by the vehicle control circuit 400, such as by firmware orsoftware in the microprocessor 4U1, to operate the toy vehicle 20 in themultiple modes and in the different shift states in the first mode ofoperation. FIG. 6D depicts the steps of a subroutine 604′ which isentered four different times at steps 604 in the main program 600 (FIGS.6A-6C) to increment and test the state of a pulse width modulator (PWM)timer (i.e. counter) to power or turn off power to either motor 410,420. The operating program 600 must be cycled through four times toincrement the PWM counter a total of sixteen times to complete one PWMpower cycle (sixteen parts) for either motor 410, 420.

[0035] FIGS. 8A-8E collectively represent a schematic diagram for asecond embodiment toy vehicle control circuit indicated generally at 800in the Figure in which FIG. 8A depicts a vehicle receiver circuit 830which receives control signals sent by the remote control/transmitter100 and amplifies and sends those signals to microprocessor 8U2 in FIG.8B. Outputs D4 and D5 from the microprocessor 8U2 are sent to a steeringmotor control circuit 805 depicted in FIG. 8C while outputs C0-C3 aretransmitted from the microprocessor 8U2 to a propulsion motor controlcircuit 815 depicted in FIG. 8D. Circuit element 8U3 is a dual operatingamplifier chip. Power is supplied to both the steering motor 410 in FIG.8C and drive motor 420 in FIG. 8D as well as the other components ofcircuit 800 via a power supply sub circuit 430 depicted in FIG. 8E whichinclude both the ON/OFF switch and a battery powered supply 435. Onedifference between circuit 800 and circuit 400 is the provision of asteering feedback through connector 860 in FIG. 8B to the vehiclemicroprocessor 8U2. The purpose of this will be described shortly.

[0036]FIGS. 9A and 9B collectively depict a second embodiment remotecontrol/transmitter circuit indicated generally at 900 which is shownessentially in FIG. 9A and indicated at 910. The only missing element isa power supply circuit 920 shown in FIG. 9B which provides two outputsVdd and Vbatt. Again, manual input elements 110 and 115 controlmomentary contacts switches 910 a, 910 b and 915 a, 915 b respectively.These switches are located on a board separate from the board supportinga microprocessor 9U1 and are mechanically and electrically coupledtogether through connectors J6 and J7.

[0037]FIG. 10A depicts part of a steering sensor indicated generally at1000 in a steering output assembly indicated generally at 1100. Outputassembly 110 includes a housing 1102 containing steering motor 410, aplurality of compound reduction gears indicated in phantom generally at1102, 1104 driving a shaft 1110 (phantom) keyed with a rotary outputmember 1120 on the housing 1102. Output member 1120 rotates in an arc,moving from side to side a wire member 1130 defining a pair of steeringarms 1132, 1134 operably coupled with separate ones of the pair of frontwheels 28 of the vehicle 20 to pivot those wheels side to side aboutvertical axes in a conventional manner to steer wheel 20. FIG. 10B showsthe output assembly 1100 with the gears 1102, 1104 and a top covercarrying the rotary output member 1120 removed. The left side ofassembly 1100 includes steering sensor 1000 while the right sideincludes steering motor 420. Sensor 1000 includes a stationary member orportion, which is indicated generally at 1010 and seen separately inFIG. 11, and a rotary member or rotating portion indicated generally at1050. The rotary member 1050 includes a plurality of connectedconcentric ring portions 1052, 1054, 1056 each containing one or moredimples 1052 a, 1054 a and 1056 a, 1056 b for the innermost ring. Thesedimples ride over the upper surface of the stationary portion 1010.Referring to FIG. 11, the stationary portion 1010 includes a circuitboard 1012 on which are mounted three electrically conductive, generallyconcentric tracks 1020, 1030 and 1040. Each track includes an outputterminal 1022, 1032, 1042, respectively on one edge of the board 1012.These three terminals connect via a suitable electrical connection (e.g.connector 860 in FIG. 8B) to microprocessor 8U2. Each track 1020, 1030,1040 is continuous around a central opening 1014 in the circuit board1012 through which the output shaft 1110 extends. Rotating portion 1050is keyed with shaft 1110 to rotate with the shaft. Rotating portion 1050is a continuous piece of electrically conductive material such as metaland electrically couples one or more of the two outer tracks 1020 and1030 with the innermost track 1040. A high level voltage is applied bythe microprocessor 8U2 through the connecter 860 to the terminals 1022and 1032. Terminal 1042 is connected to common or ground. The contactingdimples 1056 a 1056 b are in constant contact with the ring portion 1044of innermost track 1040. In contrast, dimples 1054a of ring portion 1054only contact wiper portions 1034 and 1036 of central track 1030 atcertain angular positions of rotating portion 1050. Similarly, dimples1052 a of ring 1052 only contact wiper portions 1024 and 1026 of theoutermost track 1020.

[0038] Referring to FIG. 1, dimples 1052 a, 1054 a, 1056 a, 1046 b ofrotating contact member 1050 come in contact with the tracks 1020, 1030,1040 in five different steering positions (far left indicated at 1060,near left 1062, center 1064, near right 1066, far right 1068) on printedcircuit board 1010 as member 1050 turns clockwise from far left to farright. When the rotating member 1050 is turned fully left or right,dimples 1052 a, 1054 a loose contact with tracks 1020, 1030 and logicbits “1,1” are outputted from electrical contacts 1022, 1032. When therotating member 1050 is turned clockwise from far left to left of center1062, logic bits “0,1” are outputted from electrical contacts 1022,1032. When the rotating member is in the center position 1064, logicbits “0,0” are outputted from electrical contacts 1022, 1032. When therotating member is turned to the right of center but not fully right,logic bits “1,0” are outputted from electrical contacts 1022, 1032. Whenfully right, logic bits “1, 1” are again output from contacts 1022,1032.

[0039] The states of electrical contacts 1022, 1032 are monitored byprocessor 8U2 and the speed of steering motor 410 is preferablycontrolled based on the outputted logic bits (i, i) which indicate theposition of the front wheels 28. Normally the steering motor 410operates at top speed (100%). However, with feedback provided by sensor1000, the motor 410 can be operated to prevent overshoot. FIG. 3 shows atrapezoidal velocity profile of speed versus time for the steeringfunction of a toy vehicle 20 according to a preferred embodiment of thepresent invention. Steering motor 410 may be controlled like propulsionmotor 420 by a PWM duty cycle to prevent overshoot of the steeringsystem. For example, the steering motor 410 may be driven bymicroprocessor 8U2 (or 4U1) at a higher duty cycle when going from aleft or right turn to a turn in the other direction (e.g., from far leftto far right) and at a lesser duty cycle when going from a centerposition to right or left and vice versa. When logic bits “0, 1” aredetected as the rotating member 1120 turns from center position (0, 0)to the left and passes the near left wipers 1024, 1026, or when logicbits “1, 0” are detected as the output member 1120 and rotary member1050 turn to the right and pass the near right wipers 1034, 1036, therate of the steering motor and front wheel rotation is reduced to 50% toavoid overshooting its destination (far left or far right). Preferablytoo, the speed of the propulsion motor 420 can further be reducedautomatically by the processor 8U2 when the processor 8U2 detects that aturn of the toy vehicle 20 is in progress to automatically slow thevehicle to a speed less than maximum while making the turn.

[0040] With a start and end point considered in a closed loop system,speed of the steering motor 410 in the toy vehicle 20 can be varied sothat steering follows a trapezoidal profile as shown in FIG. 3, i.e.start from zero and reach a maximum turning rate, and then slowed toreduce its rate of rotation so that steering system momentum isdissipated and the steering system does not overshoot its target. Whenthe command to steer to a new position is given, firmware operating inconjunction with microprocessor 8U2 (or 4U1) will identify the currentsteering position and move at a higher rate and duty cycle (e.g., 100%duty cycle) when the commanded steering position is more than onesteering position away from (i.e., other than adjacent to) its currentposition. For example, in going from a left turn to a right turn throughconsecutive outputs (1, 1), (0, 1), (1, 1), (1, 0) to (1, 1), the motor410 may be driven at high speed (100% duty cycle) until center position(0, 0) or near right (1, 0) is encountered and the motor 410 then drivenat a lower speed (e.g., 50% duty cycle) until far right (1, 1) issensed.

[0041] Steering control can be further refined if the steering functionis spring centered, i.e. a single torsion spring or pair of compressionor tension springs (none depicted) used to drive the rotary outputmember 1120 to the straight forward position. Then the microprocessor8U2 (or 4U1) can be configured by programming to account for action ofthe spring(s). For example, turning from left to right, themicroprocessor 8U2 may drive at high level and low level in moving morethan one steering position (e.g. left-right) or only one steeringposition (e.g. center left/right), respectively, from the presentposition and at different speeds if moving with or against a spring. Forexample, movement left to right or vice versa can begin at full speed(100% duty cycle) and transfer to first low speed (e.g. 50% duty cycle)from the center position (0, 0) to the far right position to driveagainst the centering spring in the latter part of the movement. Ingoing from right or left to center with spring assistance, the motor 410is operated at a second, lower speed (e.g., 37.5% duty cycle), whereas,while going from center to left or right against a spring, the motor 410is operated at the first low speed (e.g., 50%).

[0042] A spring loaded steering function of the toy vehicle 20 may alsoincorporate a target pad timeout period which monitors the time it takesfor the sensor 1000 to reach a particular steering position (center,near left, far left, near right, far right). If the position is notreached within a predetermined period of time, the power to the motor410 is turned off and the spring(s) will return the steering outputnumber 1120 to the center position. If the steering position does notreturn to the center position, the microprocessor 8U2 (or 4U1) isalerted that the steering is misaligned and electromechanicallyre-centers the steering.

[0043] Preferred transmitter code used in a remote control/transmitter100 operating in accordance with the present invention is located onpages A-1 through A-53 of the attached Appendix incorporated byreference herein. Preferred receiver code used in a toy vehicle 20operating in accordance with the present invention is located on pagesA-54 through A-77 of the Appendix.

[0044] In addition to duty cycle control in the vehicle 20, speedcontrol of the vehicle 20 could be performed by the remotecontrol/transmitter 100 by duty cycle transmission of a propulsion orsteering signal (i.e. transmit the signal(s) several times followed by aperiod with no signal) or by varying the rate at which the propulsionsignal is transmitted (e.g., every 10, 15 or 20 millisecond). Of course,the microprocessor of the toy vehicle 20 would also have to beappropriately configured to operate with such a duty cycle arrangement.

[0045] It will be appreciated by those skilled in the art that changescould be made to the embodiments described above without departing fromthe broad inventive concept thereof. It is understood, therefore, thatthis invention is not limited to the particular embodiments disclosed,but it is intended to cover modifications within the spirit and scope ofthe present invention.

What is claimed:
 1. A toy vehicle remote control transmitter unitcomprising: a housing; a plurality of manual input elements mounted onthe housing for manual movement; a microprocessor in the housingoperably coupled with each manual input element on the housing; a signaltransmitter operably coupled with the microprocessor to transmitwireless control signals generated by the microprocessor; and whereinthe microprocessor is configured for at least two different modes ofoperation, the microprocessor being configured in one of the at leasttwo different modes of operation to emulate manual transmissionoperation of the toy vehicle by being in any of a plurality of differentgear states and to transmit through the transmitter forward propulsioncontrol signals representing different toy vehicle speed ratios for eachof the plurality of different gear states, the microprocessor furtherbeing configured to be at least advanced through the plurality ofdifferent consecutive gear states by successive manual operations of atleast one of the manual input devices.
 2. The remote control transmitterunit of claim 1 wherein the microprocessor is configured to furthergenerate the forward propulsion control signals for the toy vehicle inresponse to manual operations of the one manual input device.
 3. Theremote control transmitter unit of claim 2 wherein the microprocessor isfurther configured to respond to two successive changes of state of theone manual input element within a predetermined period of time to changea current gear state of the microprocessor to a next consecutive gearstate.
 4. The remote control transmitter unit of claim 1 furthercomprising a sound generation circuit with a speaker controlled by themicroprocessor and wherein the microprocessor is programmed to generatesound effects controlled at least in part by the current gear state ofthe microprocessor.
 5. The remote control transmitter unit of claim 1wherein the microprocessor is configured to respond to a propulsioninput element of the plurality of manual input elements to generate theforward propulsion control signals for the toy vehicle and wherein themicroprocessor is configured for at least a second mode of operationwherein the microprocessor responds to the propulsion input element togenerate only a single forward propulsion control signal with a maximumforward speed ratio of the toy vehicle under any mode of operation ofthe remote control transmitter unit.
 6. The remote control transmitterunit of claim 14 wherein the forward propulsion control signalsgenerated by the microprocessor include at least a variable duty cyclecomponent, each transmitted duty cycle component corresponding to one ofa plurality of predetermined speed ratios of the toy vehicle.
 7. Theremote control transmitter unit of claim 6 in combination with the toyvehicle, the toy vehicle including a receiver circuit, a toy vehiclemicroprocessor coupled with the receiver circuit, a variable speedsteering motor and a variable speed propulsion motor, each motor beingoperably coupled with the vehicle microprocessor, and the vehiclemicroprocessor being configured to operate the variable speed propulsionmotor at a duty cycle corresponding to the variable duty cycle componentof the propulsion control signals.
 8. The combination of claim 7 whereinthe remote control unit microprocessor is configured to generate andtransmit steering control signals to the toy vehicle and wherein the toyvehicle microprocessor is configured to control the steering motor inresponse to the steering command signals and to a current steeringposition of the toy vehicle.
 9. The combination of claim 8 wherein themicroprocessor is further configured to control the steering motor at afirst speed where a new steering position in a steering control signalis adjacent to a current steering position of the toy vehicle and atsecond speed greater than the first speed where the new steeringposition is other than adjacent to the current steering position.